Pneumatic capsule separator

ABSTRACT

A mass of identical capsules disposed in a single layer and each containing a charge of medicament flows by gravity down an inclined chute. Each capsule is intended to contain a prescribed standard amount of medicament which, by weight and composition, is identical to the charges in all the other capsules. Incompletely charged capsules, being lighter than the others, are blown out of the layer by a stream of air which deposits them in a collection chamber from which they are removed by suction to a point of discharge.

United States Patent 72 Inventor Rich ardQBehling Goshen, N.Y. [21]Appl. No. 853,808 [22] Filed Aug. 28, 1969 [54] PNEUMATIC CAPSULESEPARATOR 8 Claims, 6 Drawing Figs.

[52] U.S.Cl

[56] References Cited UNITED STATES PATENTS 1,987,640 1/1935 Rothgarm.209/117 X 3,097,161 7/1963 Dudyak 209/137 X 3,429,438 2/1969 Palmen eta1. 209/137 Primary Examiner-Allen N. Knowles Attorney-Townshend &Meserole ABSTRACT: A mass of identical capsules disposed in a singlelayer and each containing a charge of medicament flows by gravity downan inclined chute. Each capsule is intended to contain a prescribedstandard amount of medicament which,

209/74, by weight and composition, is identical to the charges in allthe 209/l21,209/11S [51] Int. Cl B071: 13/10 [50] Field of Search othercapsules. incompletely charged capsules, being lighter than the others,are blown out of the layer by a stream of air 209/ 1 15, which depositsthem in a collection chamber m which they are removed by suction to apoint of discharge.

PATENIED um I 2 H371 SHEEI 1 OF RICHARD C. BEHLING ATroRNEm PATENTEU umI 2 l97| saw 2 BF 2 INVENTOR RICHARD C. BEHLING ATTORNEYS,

1 PNEUMATIC CAPSULE SEPARATOR BACKGROUND In the commercial massproduction or capsules and/or pellets intended to contain or compriseequal prescribed amounts, by weight, of identical composition material,the

pharmaceutical industry finds it inevitable that some will lacksufficient material to meet the required weight standard or itspermissible tolerances. Those must be removed before the product can bemarketed. The prior art, best epitomized in U.S. Pat. No. 3,097,16I toDudyak, teaches pneumatic separation and sorting of a mass of capsulessliding by gravity down an inclined chute by projecting a blast of airinto the mass in such volume, pressure, and direction that it lifts outof and above the moving mass only those lighter capsules which do notcontain the prescribed weight of medicament. Those capsules whichcontain the prescribed quantity, by weight, of medicament are too heavyto be lifted by the air blast and so are not separated from the mass.The lighter weight capsules are carried by the air blast against amechanical divider plate which directs them into a separate path oftravel and into a collection receptacle. 7

Otherwise stated: The prior art teaches pneumatic separation ofincompletely charged capsules by lifting them in an airstream whichcarries them into impact against mechanical guide means which divertsthem into a path of travel separate from that of the main body and inwhich they travel by gravity to a point of discharge. However, the priorart does not teach the use of suction to divert the airlifted capsulesinto a path of travel different than the path of travel of the mainbody.

Prior to the advent of the present invention, the art has relied solelyupon the force of a stream of air under positive pressure to liftincompletely charged capsules from the main body of the mass and carrythem away. This requires very careful regulation of the air pressure. Itthe force of the airstream is too great all or a majority of the mass ofcapsules will be lifted from the main body and discarded as rejects. Ifthe air pressure is not high enough to lift out the incompletely charged(lighter) capsules they will not be separated from the main body. Forthat reason the prior art has been concerned only with regulation of theairblast pressure at its source; the

objective being to maintain an airblast stream at a force suflicient tolift incompletely charged capsules out of the main body and carry themto an elevation above the main body at which they are either diverted bymechanical guide means or fall by gravity into a path of travel leadingto a point of discharge as rejects.

In the pneumatic capsule separators of the prior art the positivepressure airstream must not only exert enough force to lift incompletelycharged capsules out of the main body but also it must be sufficientlypowerful to perform the additional function of conveying those capsulesbodily over the distance between their point of separation from the mainbody and the point at which they are mechanically diverted or fall bygravity from the airstream. This added burden of conveying after liftingnecessarily requires that the airstream pressure be greater than thepressure needed only to lifi the incompletely charged capsules from themain body; which makes it an extremely difficult matter to regulate thevery small pressure differential so that the force of the airstream willnot lift some acceptable capsules for discharge together with therejects.

SUMMARY OF THE INVENTION The present invention follows prior artpractice to the extent that it makes use of a stream of air underpressure blowing upwardly through a mass of capsules or pellets movingin a single layer, thereby separating out and lifting above the surfaceof the layer all those capsules or pellets which are, in weight, below aprescribed standard. It departs from and improves upon the aforesaidprior art practice in the manner and means by which imperfect capsulesor pellets are caused to be lifted out of the moving layer, and in themanner and means by which the elevated capsules or pellets are removedand conveyed to a point of discharge as rejects.

In the practice of the present invention, the pressure of the airstreamused to separate the imperfect capsules or pellets is just enough tolift them above the upper surface level of the moving layer, at whichelevation they are subjected to suction which pulls them to a point ofdischarge. The separation and removal of the rejects is accomplished bythe push-pull action of air under pressure combined with suction. Thiscombination, employed as herein disclosed, effectively preventsinadvertent carryover of acceptable capsules or pellets for discharge asrejects.

przscalvnou or THE oaswmos FIG. I is a side elevation of a pneumaticseparator embodying the present invention.

FIG. 2 is a sectional view on line 2-2 of FIG. I. FIG. 3 is afragmentary sectional view on line 3-3 of FIG. 1 J

FIG. 4 is a sectional view on line 4-4 of FIG. 2.

FIG. 5 is a sectional view on line 5-5 ofFIG. 2.

FIG. 6 is a fragmentary sectional view on line 6-6 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the embodiment "of theinvention as herein shown and described, a mass of charged capsules isfed from a supply source 10 onto the upper end of a downwardly inclinedchute having a flat bottom II and parallel upstanding sidewalls l2.Thechute is inclined at an angle of substantially 45 and the height ofits sidewalls is only slightly greater than the thickness of a capsule.TI-Ie capsules are fed from the supply source in such manner that theyform a single layer on the flat bottom 11 of the chute and slide thereonby gravity beneath a hood 13 covering the open top of the chute toprevent loss of capsules by bouncing or jostling. The roof of the hoodis inclined downwardly from its upstream end to its downstream end, atwhich end it is proximate the top edges of the chute sidewalls 12. Thelower end of the chute carries an extension 14 for discharge of capsulesinto a bin 15.

Intermediate the lower end of the chute and the hood I3 chute pasesthrough a separation station constituted of an air pressure manifold 16carried by the chute and extending therefrom beneath its bottom VII, anda tubular suction manifold I7 also carried by the chute and extendingtherefrom above its top opposite the air pressure manifold 16. The twomanifolds are aligned axially on an axis that is perpendicular to theplane of the flat chute bottom .11 and which panes through the center ofan air aperture 18 through the bottom of the chute. Aperture 18 is inthe form of a narrow slot with parallel sides that extends transverselyacross the full width of the chute bottom between its sidewalls andperpendicular thereto. The width of the slot is less than the overallthickness of a capsule; which assures that all capsules passing over theslot will bridge it and cannot become lodged therein.

Air pressure manifold 16 is a boxlike chamber in open communicationthrough its bottom with the outlet of an air blower I9 secured to anddepending from the body of the chute assembly by bracket means 20. Thetop edge of the box seats a complemental frame 21 in which is mounted anair guide member 22. This guide as here shown is formed as a deep gridin which the crossed bars are walls circumscribing air channels ofuniform square cross section and'parallel to the longitudinal axis ofalignment of the two manifolds l6 and 17. The top face of the grid 22 isflush with the top face of its mounting frame 2] and both are inengagement with the undersurface of the chute bottom 11, as shown inFIG. 3. Grid frame 21 is fixedly attached to the air pressure manifold16 between an opposed pair of its walls which, as shown in FIG. 5,extend above the chute assembly at the sides thereof. The inner faces ofthese walls have secured thereto fixed internal flange strips 23 whichseat upon the top edges of the chute sidewalls l2 and provide supportfor the manifold. A stove bolt 24 (FIG. 6) threaded in a bracket 25fixed to and depending from the bottom 11 of the chute downstream fromthe air pressure manifold 16 provides an adjustable stop bearing on awall of the manifold to hold it against downward sliding movement on thechute and enables adjustment of .the manifold longitudinally of thechute to center the airflow guide grid 22 relative to the air passageslot 18.

Tile suction manifold 17, as here shown, is a chamber mounted at itsbase on the chute assembly over the top thereof and in axial alignmentwith the air pressure manifold 16. It seats at its base on the topedgesof the chute sidewalls 12 in open communication with the chute, andis coupled at its upper end to a flexible hose 26 that is a conduitwhich leads to and is in communication with theinlet tube 27 of asubstantially boxlike receptacle 28 for capsules rejected at theseparation station. A pipe 29 extends through the bottom of thereceptacle 28 with its upper end spaced slightly below the top of thereceptacle and with its lower end in connection with a conduit 29 whichleads to a source of suction 30.

The downstream wall of the suction manifold 17 carries on its inner facean inclined baffle 31 which is adjustable to a selective elevation abovethe top surface level of a layer of capsules sliding down the chute.

METHOD OF OPERATION In the practice of the present invention, a mas ofmedicament-charged capsules is fed from the supply source onto the upperend of the flat bottom 11 of the chute. The capsules form a single layeron the chute bottom andslide by gravity down the chute and into theseparation station. As they pass over the air slot 18 they are subjectedto the action of a stream of air issuingupwardly through the slot fromthe manifold 16 underpressure from the blower 19. The blower pressure issuch that the force of the airstream issuing from the slot 18 is justenough to lift out of the moving layer of capsule all those which weighless than a prescribed standard weight and present them to the closelyoverlying intake of the suction manifold 17 at its base.

Those capsules lifted from the main body and presented to the intake ofthe manifold 17 are sucked into the manifold chamber and then throughconduit 26 and tube 27 into the rejects collection receptacle 28 fromwhich they may be removed through an access port (not shown). Thosecapsules which meet the prescribed weight standard are too heavy to belifted by the airstream issuing from the slot 18 and in consequence willslide across the slot and continue their travel down the chute to dropinto the acceptable capsule storage bin 15.

When the capsules being processed are of less than conventionalthickness, the baffle 31 may be lowered between the sidewalls of thechute to a position at which its leading edge is just above the toplevel of the capsule layer, so that it picks up the lifted capsules andguides them into the suction manifold.

[t is apparent from the foregoing description that incompletely chargedcapsules, being lighter than the prescribed standard individual weightfor the mass of capsules being processed, will be airlifted (pushed)above the moving layer of heavier standard weight capsules to a positionfrom which they are pulled by suction into a path of travel separatefrom the path of travel of the heavier capsules. In effect, separationis accomplished by the simultaneous application of air under pressureagainst one face of the moving layer of capsules and suction to itsopposite face.

The principles upon which this invention is bases are such thatsubstantial variations from the structure shown and described herein maybe made. For example: the chute, being a stationary conveyor, could bereplaced by a travelling screen belt conveyor disposed horizontallyinstead of at an incline. Tl-le inclined chute arrangement is preferredbecause it is far less expensive to install and maintain than atraveling belt conveyor and does not require the expenditure of powernecessary to drive a belt.

I claim:

' 1. Apparatus for pneumatically separating and sorting a mass ofcapsules of identical configuration and containing a filler material ofthe same composition, which comprises, in combination: a capsule-feedingstation; a capsule collection station; a capsule-separating stationbetween the feeding and collection stations; a conveyor for passing asingle layer mass of the capsule from the feeding station, through theseparating station and to the collection station; means at theseparating station operative to blow a confined stream of air throughone face of the conveyor at substantially a right angle thereto; meansalso at the separating station operative to apply suction adjacent theoppodte face of the conveyor over an area corresponding to the crosssectional area of the confined airstream and in alignment therewith;whereby to pick up capsules blown from a layer of capsules on theconveyor; a source of suction; and a conduit connecting said source ofsuction and said suction-applying means for carrying away capsules blownfrom the conveyor by force of the airstream.

2. In the apparatus of claim 1, said conduit including acapsule-trapping chamber located between the source of suction and thesuction-applying means.

3. Apparatus for sorting and separating properly filled capsules fromimproperly filled and therefore lighter capsules, which comprises, incombination; aninclined chute; means for feeding a mass mixture of thecapsules to the upper end of the chute for passage by gravity down thechute to discharge at its lower end; means for blowing a stream of airthrough the moving mass of capsules at an angle to the path of travel ofthe mass, thereby separating the improperly filled lighter capsules fromthe properly filled heavier capsules; and suction means operative in thearea of influence of the'sirstream to draw off the separated lightercapsules and convey them away from the mas of capsules movingby gravitydown the chute. Y

4. in the apparatus of clairn'3, the angle of the airstream relative tothe path of travel of the mass of capsules being substantially 5. In theapparatus of claim 3, said suction means including a manifold chamberhaving an intake disposed within the area of influence of the airstream.

6. In the apparatus of claim 3, the chute having in its bottom a narrowslot for the upward passage of air from the air blowing means; an airpressure manifold beneath the chute bottom and having an outlet incommunication with the slot and an inlet in communication with the airblowing means; and said suction means including a suction manifoldhaving an intake spanning the top of the chute immediately above theslot.

7. The method of separating and sorting a mass of capsules of uniformshape and thickness into a group in which all the capsules areindividually of the same predetermined standard weight, and into adifferent group consisting of capsules of less than the standard weight,which comprises: passing the mass of capsules by gravity down aninclined chute in a path of travel leading to a point of collection;blowing through the moving mass a stream of air at such volume,velocity, and direction that it carries out of and separates from themass only those capsules which are of less than the standard weight;applying suction to the separated capsules as they leave the mass andthereby diverting them into a path of travel different than the pathfollowed by the standard weight capsules and leading to a differentpoint of collection.

8. The method of separating and sorting a mass of capsules of uniformshape and thickness into a group in which all the capsules areindividually of the same predetermined standard weight, and into adifferent group consisting of capsules of less than the standard weight,which comprises: blowing upwardly through the bottom of an inclinedchute an unbroken stream of air extending transversely entirely acrossthe chute at a unifon'n thickness and velocity such that it allows thepassage therethrough only of capsules having the standard weight;

passing the mass of capsules in a single layer down the chute

1. Apparatus for pneumatically separating and sorting a mass of capsulesof identical configuration and containing a filler material of the samecomposition, which comprises, in combination: a capsule-feeding station;a capsule collection station; a capsule-separating station between thefeeding and collection stations; a conveyor for passing a single layermass of the capsule from the feeding station, through the separatingstation and to the collection station; means at the separating stationoperative to blow a confined stream of air through one face of theconveyor at substantially a right angle thereto; means also at theseparating station operative to apply suction adjacent the opposite faceof the conveyor over an area corresponding to the cross-sectional areaof the confined airstream and in alignment therewith; whereby to pick upcapsules blown from a layer of capsules on the conveyor; a source ofsuction; and a conduit connecting said source of suction and saidsuction-applying means for carrying away capsules blown from theconveyor by force of the airstream.
 2. In the apparatus of claim 1, saidconduit including a capsule-trapping chamber located between the sourceof suction and the suction-applying means.
 3. Apparatus for sorting andseparating properly filled capsules from improperly filled and thereforelighter capsules, which comprises, in combination; an inclined chute;means for feeding a mass mixture of the capsules to the upper end of thechute for passage by gravity down the chute to discharge at its lowerend; means for blowing a stream of air through the moving mass ofcapsules at an angle to the path of travel of the mass, therebyseparating the improperly filled lighter capsules from the properlyfilled heavier capsules; and suction means operative in the area ofinfluence of the airstream to draw off the separated lighter capsulesand convey them away from the mass of capsules moving by gravity downthe chute.
 4. In the apparatus of claim 3, the angle of the airstreamrelative to the path of travel of the mass of capsules beingsubstantially 90*.
 5. In the apparatus of claim 3, said suction meansincluding a manifold chamber having an intake disposed within the areaof influence of the airstream.
 6. In the apparatus of claim 3, the chutehaving in its bottom a narrow slot for the upward passage of air fromthe air blowing means; an air pressure manifold beneath the chute bottomand having an outlet in communication with the slot and an inlet incommunication with the air blowing means; and said suction meansincluding a suction manifold having an intake spanning the top of thechute immediately above the slot.
 7. The method of separating andsorting a mass of capsules of uniform shape and thickness into a groupin which all the capsules are individually of the same predeterminedstandard weight, and into a different group consisting of capsules ofless than the standard weight, which comprises: passing the mass ofcapsules by gravity down an inclined chute in a path of travel leadingto a point of collection; blowing through the moving mass a stream ofair at such volume, velocity, and direction that it carries out of andseparates from the mass only those capsules which are of less than thestandard weight; applying suction to the separated capsules as theyleave the mass and thereby diverting them into a path of traveldifferent than the path followed by the standard weight capsules andleading to a different point of collection.
 8. The method of separatingand sorting a mass of capsules of uniform shape and thickness into agroup in which all the capsules are individually of the samepredetermined standard weight, and into a different group consisting ofcapsules of less than the standard weight, which comprises: blowingupwardly through the bottom of an inclined chute an unbroken stream ofair extending transversely entirely across the chute at a uniformthickness and velocity such that it allows the passage therethrough onlyof capsules having the standard weight; passing the mass of capsules ina single layer down the chute by gravity into the up-blowing airstreamwhereby the standard weight capsules will pass through the airstream andcontinue down the chute to a collection point, and whereby the airstreamwill lift out and separate and separate from the mass those capsuleswhich are below the standard weight; and conveying the separated lightercapsules to a different point of collection by means of suction appliedto the lighter capsules as they are separated from the mass.